By chemical treatment with benzoyl peroxide (BPO, C14H10O4), oxygen functional groups can be introduced into the surface of the lead-film. To understand the effect of oxygen functional groups into the surface of the lead-film on the adhesion strength between Ni metal lead-tap and lead-film, peel test was performed. As a result, initial adhesion strength between them was improved by 38% when the BPO-treated lead-film was used. In addition, after the BPO-treated lead-film and non-treated lead-film were attached on the lead-tap, respectively, and then they were immersed in a conventional electrolyte of LiB at 80 ℃ for 24 h, the adhesion strength of the lead-tap with the BPO treated lead-film was improved by 20% compared to the lead-tap with the non-treated lead-film.

본 논문에서는 파우치 타입 리튬이차전지에 사용되는 Ni 금속 리드-탭과 리드-필름 간의 결착력 향상을 위한 화학적 표면처리 연구를 수행하였다. 과산화벤조일(BPO)을 리드-필름에 적용할 경우 다량의 산소 관능기가 필름 표면에 형성되는 것을 확인하였다. BPO 표면처리를 통해 표면에 형성된 산소관능기가 금속 Ni 리드-탭과의 결착력 향상에 미치는 영향을 관찰하기 위해 점착력 실험(peel test)을 수행하였다. 초기 점착력의 경우 표면처리 되지 않은 리드-필름 대비 Ni 금속 리드-탭과의 결착력이 38% 향상되었으며 상용 리튬이차전지에 적용되는 전해액에 80 ℃ 온도에서 24시간 함침시킨 후 점착력을 측정한 결과 20% 향상됨을 확인하였다.

Keywords: lithium-ion battery, lead-tap, lead-film, adhesion strength, surface treatment